The development of high-brightness solid state light sources, such as but not limited to light emitting diodes (LEDs) and the like, has led to use of such devices in various lighting fixtures. In general, a solid state light source-based lamp operates in a fundamentally different way than an incandescent, or gas discharge lamp, and therefore may not be connectable to existing lighting fixtures designed for those lamp types. A driver circuit may be used, however, to allow use of an solid state light source-based lamp as a retro-fit for existing lighting fixtures.
The driver circuitry for an solid state light source-based lamp generally converts an alternating current (AC) input, such as a 120V/60 Hz line input or input from a dimmer switch, to a stable direct current (DC) voltage used for driving the solid state light source-based lamp. Such circuitry may incorporate a rectifier for receiving the AC input and a DC-DC converter circuit. The DC-DC converter circuit may receive an unregulated DC output from the rectifier and provide a stable, regulated DC output to the solid state light source-based lamp.